How to identify a gravity or pumped vented cylinder

[Koosa]

My cylinder has developed a leak an needs replacing, its a vented indirect system with a tank in the loft but I didn't realise there are replacement cylinders for gravity or pumped systems.

How can I tell which mine is - it seems like its an original set up from the 80's. There is a pump next to the cylinder but I think that just for the cylinder

Edit - to upload pics of cylinder and pump at the boiler. The feed and return pipes are in the rear corner of the cupboard but are 22mm

 

[CBW]

If there’s a pump, it’s fully pumped. Gravity wouldn’t have a pump at all.

 

[flameport]

How can I tell which mine is

Add a photo here of the cylinder, surrounding items and boiler.

However gravity would usually mean an ancient floor standing boiler with 4 separate pipes, at least 2 of which are large 1 inch or more diameter, controls which have the choices of HW and heating or HW only (no heating only), and hot water from the outlets at temperatures hotter than the surface of the sun.

 

[Koosa]

Photos added

 

[CBW]

Yep, seems to be fully pumped. Good job you’re getting a new cylinder, as that one is uninsulated

 

[Koosa]

Thanks Chris - I stripped its jacket off to see the leak and the pipe locations - damn thing makes it like a sauna when the waters on

 

[JohnD]

Consider if it is big enough. I like a cylinder that can run a bath (about 100 litres) and still have enough for washing up and a shower.

Moden cylinders are so well insulated that heat loss is not much of a problem, and it is more economical to run your boiler once or twice a day, to heat the entire thing, rather than let it fire up every time someone washes their hands.